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<div class="section" id="module-quippy.units">
<span id="units-and-physical-constants"></span><h1>Units and physical constants<a class="headerlink" href="#module-quippy.units" title="Permalink to this headline">¶</a></h1>
<p>This module holds a collection of our units and conversion factors.
We use Angstroms (<span class="math notranslate nohighlight">\(\mathrm{\AA}\)</span>), eV, and femtoseconds (fs).</p>
<ul class="simple">
<li>Length:   Angstroms, <code class="docutils literal notranslate"><span class="pre">a.u.</span> <span class="pre">*</span> <span class="pre">BOHR</span></code></li>
<li>Energy:   eV,        <code class="docutils literal notranslate"><span class="pre">a.u.</span> <span class="pre">*</span> <span class="pre">HARTREE</span></code></li>
<li>Time:     fs</li>
<li>Mass:     <span class="math notranslate nohighlight">\(E T^2/L^2\)</span> = <code class="docutils literal notranslate"><span class="pre">a.u.</span> <span class="pre">*</span> <span class="pre">HARTREE</span> <span class="pre">*</span> <span class="pre">AU_FS**2</span> <span class="pre">/</span> <span class="pre">BOHR**2</span></code></li>
</ul>
<p>Module contents for <a class="reference internal" href="#module-quippy.units" title="quippy.units: Units and physical constants"><code class="xref py py-mod docutils literal notranslate"><span class="pre">quippy.units</span></code></a>:</p>
<p class="rubric">Attributes</p>
<table border="1" class="docutils">
<colgroup>
<col width="62%" />
<col width="38%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Name</th>
<th class="head">Value</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">CPLX_ZERO</span></code></td>
<td>(0.0, 0.0)</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">BOLTZMANN_K</span></code></td>
<td>8.6173303e-05</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">RADIANS_PER_DEGREE</span></code></td>
<td>0.0174532925199</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">VACUUM_C</span></code></td>
<td>299792458.0</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">GPA_TO_EV_A3</span></code></td>
<td>0.00624150912588</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">EV_A3_IN_GPA</span></code></td>
<td>160.21766208</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">ONESECOND</span></code></td>
<td>1e+15</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">N_A</span></code></td>
<td>6.022140857e+23</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">HBAR_EVSEC</span></code></td>
<td>6.582119514e-16</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">AU_FS</span></code></td>
<td>0.0241888432628</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">have_cp2k</span></code></td>
<td>1</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">BOHR</span></code></td>
<td>0.52917721067</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">KCAL_MOL</span></code></td>
<td>0.0433641039006</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">have_lotf</span></code></td>
<td>1</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">GRAM</span></code></td>
<td>0.001</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">DEBYE</span></code></td>
<td>0.208194334425</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">HBAR</span></code></td>
<td>0.6582119514</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">CPLX_ONE</span></code></td>
<td>(1.0, 0.0)</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">ONESECOND_AU</span></code></td>
<td>4.13413733405e+16</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">MASSCONVERT</span></code></td>
<td>103.642695707</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">ELEM_CHARGE</span></code></td>
<td>1.6021766208e-19</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">EPSILON_0</span></code></td>
<td>0.00552634940621</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">GPA</span></code></td>
<td>160.21766208</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">CUBIC_BOHR</span></code></td>
<td>0.0102908583961</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">EPSILON_0_AU</span></code></td>
<td>8.854187817e-12</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">PI</span></code></td>
<td>3.14159265359</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">have_netcdf</span></code></td>
<td>1</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">HBAR_AU</span></code></td>
<td>1.0</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">RYDBERG</span></code></td>
<td>13.60569301</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">INVERSE_CM</span></code></td>
<td>0.000123984197388</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">DEGREES_PER_RADIAN</span></code></td>
<td>57.2957795131</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">CPLX_IMAG</span></code></td>
<td>(0.0, 1.0)</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">HARTREE</span></code></td>
<td>27.21138602</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">ELECTRONMASS</span></code></td>
<td>9.10938356e-31</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">ELECTRONMASS_GPERMOL</span></code></td>
<td>0.000548579909188</td>
</tr>
</tbody>
</table>
</div>


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